Core C is a new core to this PPG. Previously, statistically related services were offered to PPG investigators through Core A, the administrative core. Core C is now an independent core, due to increased demand for such services. Core C will focus primarily on biostatistics and data management (BDM) including measurement. However, Core C also incorporates analytical components of "modeling" and image analysis. Our objective is to insurer that appropriate statistical expertise is integrated into each project from inception (e.g., design, power analysis), to implementation (e.g., measurement evaluation), to completion (statistical analysis, interpretation, and reporting). Core C will provide the following services: 1. Assistance in the design of studies. A major goal of the BDM team is to enable investigators to obtain advise on experimental design before they begin their primary projects or new sub-projects. 2. Management of an electronic database of all PPG-generated data, ensuring secure storage and back up, quality and accuracy of entry, and timely provision of data files for subsequent analyses. 3. Collaboration with investigators and Core in evaluating and maintaining the reliability and validity of measured used in the PPG. 4. Assistance in identifying, obtaining, and using software for statistical analysis and related tasks. 5. Consultation on the choice, implementation, and interpretation of statistical procedures that investigators choose to conduct themselves. 6. Conduct of more complex statistical analyses as needed (e.g. simulation studies, mixed models). 7. Collaboration on preparing statistical and related aspects of manuscripts. 8. Fostering greater development and use of expertise in modeling and image analysis procedures. Eight scientists including five Ph.D. statistician-data analysts will provide support through Core C. By relying on a team of statistician-data analysts with diverse areas of specialization, we can support the projects in virtually any area of statistical analysis.